Roll crusher with means to axially adjust the position of at least one roll



Feb. 28, 1956 P. HANNES 2,736,504 ROLL CRUSHER WITH MEANS TO AXIALLY ADJUST THE POSITION OF AT LEAST ONE ROLL Filed June 7, 1954 IN VEWT OR PA 04 m4 was M @1494; a W

A 770 R NE) United States Patent ROLL CRUSHER WITH MEANS TO AXIALLY AD- JUST THE POSITION OF AT LEAST ONE ROLL Paul Hannes, Esseu-Steele-Horst, Germany, assignor, by

mesne assignments, to Koppers Company, Inc., Pittsburgh, Pa., a corporation of Delaware The rolls of roll crushing mills, more especially of highspeed roll crushing mills, are subject to heavy wear. After having been in use for a certain period of time, more or less deep grooves become apparent, which jeopardize the uniform crushing of the granular material. This wear is also not capable of being substantially reduced by the rolls being provided with hard steel casings, for example, austenitic manganese steel casings. The grinding rolls therefore have to be frequently reground.

The object of the invention is to arrange the grinding rolls of roll crushing mills in such manner that the wear is substantially reduced. According to the invention, the rolls of roll crushing mills are mounted to be axially displaceable longitudinally relatively to one another. By means of such a mounting, with which the grinding rolls are axially moved longitudinally relatively to one another at certain time intervals, the result is attained that the wear does not take effect unilaterally in the formation of grooves, but is distributed as far as possible uniformly over the width of the grinding rolls. In this manner, grinding down of the grinding rolls, even if not entirely avoided, is only necessary at considerably longer intervals.

The relative longitudinal axial displacement necessary, due to the arrangement of the grinding rolls, according to the invention may be carried out by means of longitudinal axial movement of both rolls, as well as by longitudinal axial movement of only one roll. Advantageously, according to the invention, the bearings for the shaft, while resting against a shoulder of the shaft carrying the grinding roll, is pivotally connected to a pair of levers each of which, at one end are also pivotally connected at a fixed point to the grinding roll frame and each of which at their other ends are pivotally connected to a shaft which is parallel to the axis of the bearings and axially adjustable, as by means of a hand wheel or the like. By means of this lever arrangement, one of the two grinding rolls is longitudinally moved axially a certain distance at predetermined time intervals.

According to the invention, the contemplated axial displaceability of the rolls is not limited solely to the preferred hand embodiment, since it may also be effected automatically, for example, by a separate electric motor. However, the drive may also be effected by the driving motor for producing the rotation of the roll, by way of a clutch, which is, perhaps, to be engaged at predetermined time intervals or by means of a pneumatic or hydraulic driving device.

According to the invention, the automatic relative axial displacement as contemplated is one which is further controlled by means comprising a time relay which, at adjustable time intervals, closes and opens the circuit of the electric motor for effecting the axial displacement.

The invention is illustrated by way of example in the accompanying drawing, wherein:

Figure 1 is a diagrammatic side elevation, and

Figure 2 is a top plan view of the grinding or crushing mill of Fig. 1 constructed in accordance with the invention.

The pair of grinding rolls 1, 2 are rigidly connected 2,736,504 Patented Feb. 28, 1956 to shafts 3, 4. The shafts 3, 4 are mounted in bearings 5, 6. The bearings 6 of the grinding roll 4 are fixedly arranged on a supporting frame 7 in the conventional manner. The oppositely disposed bearings 5 of the grinding roll 1 are pivotally connected each to one of the lever arms 8. The drive of the grinding rolls 1, 2 is effected by way of a V-belt pulley 9 from an electric motor which is not shown in the drawing, the drive either being a joint drive for both rolls or a separate drive being provided for each of the latter.

The lever arms 8 are of I-shape in cross-section. The vertical web is cut away at both ends. At the bottom end, the cut-out of the lever arm 8 embraces a member 12 which is arranged fast on the supporting frame 7 and about which the lever arm 8 is mounted for rocking movement on a pivot pin 11. The lever arms 8, pivotally connected on both sides of the frame to each of the bearings 5 of the grinding roll 1, are arranged to extend at an upward inclination. At the upper end, the space between the two transverse flanges of the I-shaped lever arm 8 has extending therethrough a shaft 14 through which passes a pivot pin 10. In this manner, the two lever arms 8 of the bearings 5 are displaceable by means of the shaft 14 in parallelism with the shafts of rolls 1, 2.

At one end, the shaft 14 is formed with an internal screw-thread 15, into which is screwed a screw 17 connected to a hand wheel 16. The hand wheel 16 is supported against a strut 18 connected fastto the frame 7. The shaft 14 may thus be moved parallel to the roll shaft 3 by rotating the hand wheel 16. By this means, the lever arms 8 are also displaced arcuately about pivots 11 and move the bearings 5 axially. The bearings 5 bear against an attachment in the form of collars 19, 22 of the roll shaft 3, so that when the shaft 14 is displaced in the direction of the arrow 20, the upper bearing 5 acts against the collar attachment 19 of the roll shaft 3 and shifts the latter, whereas the other lower bearing 5 acts against the corresponding collar attachment 22 of the roll shaft when the shaft 14 is displaced in the direction of the arrow 21.

As shaft 14 moves parallelly with shaft 4, the pivot between arms 8 and bearings 5 moves the bearings 5 longitudinally while allowing the bearings 5 to swivel on arms 8. Contact of rolls 1 and 2 maintains shaft 3 parallel and bearings 5 perpendicular to shafts 4 and 14, during the arcuate shifting movement of levers 8.

According to the distance chosen from the centre of the bearings 5 to the centre of the stationary hinge pin 11 passing through the fixed abutment 12, it is thus possible to effect a more or less large axial displacement of the grinding roll 1 longitudinally relatively to the fixed grinding roll 2 when the shaft 14 is displaced parallelly. This displacement of the grinding roll 1 need only be a few millimetres and may be effected at relatively large time intervals in order to obtain a uniform wear of the surfaces of the two grinding rolls 1, 2.

The hand wheel 16 is secured against unintentional turning by means of a locking nut 25.

Instead of being effected preferably by means of a hand wheel 16, the axial displacement of the shaft 14 may also be carried out within the broader aspects of the invention by means of an electric motor which operates through a suitable transmission gear on the shaft 14 and which can be stopped by a limiting stop. The electric motor may be switched on at specified time intervals by a time relay in manners conventional in the arts of other devices.

I claim:

1. Roll crushing mill for crushing coke fines and coal comprising, parallel grinding rolls with mounting means for axially displaceably mounting of at least one of the grinding rolls longitudinally one relative to another, characterized by said mounting means comprising oppositely disposed bearings resting against an attachment on a shaft which supports the grinding roll to be displaced, said bearings being pivotally connected each to one of oppositely disposed levers which are also disposed transverse to the axis of the shaft of said roll to be displaced, each lever being pivotally connected at one point at a fixed region relative to the shaft to be displaced and at an opposite point pivotally connected to a third shaft which is also axially adjustable parallelly with the aforesaid shaft of the grinding roll to be longitudinally displaced relative to another, and means for axially moving the third shaft longitudinally.

2. Apparatus as claimed in claim 1, and in which the means for axially moving the third shaft longitudinally comprises hand operable means.

References Cited in the file of this patent UNITED STATES PATENTS 

